All married, same-sex couples in the U.S. will receive federal tax benefits previously given to just heterosexual couples, the Obama administration said on Thursday.
The ruling applies even to gay couples who live in states where their union is not recognized -- so long as they were married in a state that allows same-sex marriage.
"Today's ruling provides certainty and clear, coherent tax filing guidance for all legally married same-sex couples nationwide." said Secretary Jacob J. Lew in a statement. "This ruling also assures legally married same-sex couples that they can move freely throughout the country knowing that their federal filing status will not change."
The U.S. Treasury and Internal Revenue Service announcement comes on the heels of the landmark Supreme Court ruling in June that said same-sex couples are entitled to federal benefits. The ruling struck down the 1996 Defense of Marriage Act that blocked federal recognition of gay marriage.
The ruling applies to filing status, personal and dependency exemptions, standard deduction, employee benefits, IRAs, earned income tax credits and child tax credits, according to the Treasury Department and IRS statement.
The ruling does not apply to those in registered domestic partnerships or civil unions.
Thirteen states and Washington, D.C., have legalized same-sex marriage as of August: California, Delaware, Connecticut, Iowa, Maine, Maryland, Massachusetts, Washington, Vermont, Rhode Island, New York, Minnesota and New Hampshire.
Before Thursday's ruling, same-sex couples that had married had to declare themselves as "unmarried" on federal income tax forms. The Human Rights Campaign, a civil rights organization, said that cost the average same-sex couple more than $1,000 a year in additional taxes. It also meant that gay couples could not inherit property without it being taxed.
"No family should have to worry about losing important federal rights and benefits, simply because they live in a state that doesn't recognize them as equal under the law," Chad Griffin, president of the Human Rights Campaign, said in a statement.
In the anti-marriage camp, Brian Brown, president of National Organization for Marriage, denounced the ruling in a statement.
"The Treasury Department is grossly overstepping its authority," Brown said. "The Obama administration is intent on forcing same-sex marriage on an unwilling public."